This post was published long before the Mists of Pandara Expansion.
The tips and techniques explained here may be outdated.

Warlock Spell: Curse of Agony

Here’s my visualization of the spell cast. Above is the timeline. It’s dotted in 1 second intervals with an extra dark dot at each 5 seconds to make it easier to read.

The spell is cast at time 0. It is instant cast. The “X” is the Global Cooldown (GCD) (1.5 seconds). The dotted purple/grey lines are where damage actually occurs. Assuming the dot runs for full duration it will do 12 ticks. The damage “ramps up” with most of the damage occuring in the last 4 ticks.

Assuming I have 1k bonus shadow damage each tick should hit for 151-453 for a total of ~3623.

Relevant Talents:

Amplify Curse increase damage done for next CoA by 50%, 3 min cooldown.Improved Curse of Agony 2/2 – increases the damage by 5%/10%.Contagion 5/5 – Increases the damage of Curse of Agony, Corruption and Seed of Corruption by 5% and reduces the chance your Affliction spells will be dispelled by an additional 30%Shadow Mastery 5/5 – Increase the damage dealt or life drained by your Shadow Spells by 10%